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johnny stecchino · Member

Purchased the el-cheapo Crosman Phantom 500 in 0.22. Fired gun, inconsistent groupings. Machine oil all over. Not much punch either (it's the 500 fps version). It's a diamond in the rough - no polish whatsoever.

Stripped down the rifle. Removed edges in chamber with a Dremel tool to make sure seal not damaged upon reassembly. Cleanup up all excess factory machining oil with hot water and detergent bath/rinse (all metal parts including trigger). While still hot from bath, dried and light coated with WD-40, then wiped clean - very clean with the very slightest sheen of WD-40.

Lubed new spring and new piston with light application of Fluid Film lube , changed seal too. I can't stand the moly lube "tar", I think it is crap, I use Fluid Film. It has proven itself to be a great lube for airguns, but use sparingly. Finally, it does NOT seem to cause any detonation (at least none that i can notice).

Lubed trigger with Fluid Film. Set trigger to "touchy end", not much pull need to make it fire.

Then crowned the barrel:
First, lightly clamp barrel in a vice horizontally (with plastic protectors over vice jaws) and hack saw off plastic tip (plastic part of sight, do not cut metal with hack saw). Unfortunately, it's the only way you are going to see anything, that's why you have to hack saw of the plastic. Reposition barrel vertically and insert a pellet into the barrel at the sight end - this will keep debris from falling into the barrel. Then file down the plastic until bare metal of barrel is exposed - now everything is level, plastic and barrel metal. Crown with a Dremel tool, used a fine grit conical stone, about a 60 degree cone, about 3/8 inch base. Made a deep crown by Dremeling the crown with a very, very light touch, deep into barrel. Touched crown up with fine round jeweler's file to make sure no burrs were in barrel. Popped out the pellet with gun cleaning tool (1 cotton wad with slightest touch of WD-40, and then 2 cotton wads only to clean out any WD-40). Finished by blueing the barrel tip so it all looks factory original (unfinshed raw metal doesn't look too good).

Comment: forget using a brass screw head to crown the barrel. Use a Dremel tool with a fine grit conical stone. And use a very light hand. The results are superior in every way. A deep crown seems to provide better accuracy (especially with a fine grit conical stone). not only are any barrel edges removed, but the air gets to gently wrap the the pellet in an expanding barrel - less of a shock when exiting the barrel.

Reassembled, added 4 stainless steel washers between piston and spring guide - more preload and allows spring to twist easier, light lube with Fluid Film. Used Locktite Blue on body bolts and barrel bolt.

Result: 1 cm groupings at 10 meters, punch through 1/2 inch plywood, Crosman Premier hollow points used.

What happened:
1. major power increase from new components (spring and piston),
2. accuracy increase from crowned barrel.

The deep crowning seemed to have been very beneficial, groupings are tight (about 1 cm at 10 meters). Performance like a more expensive German rifle with open sights for 1/3 to 1/4 the cost + elbow grease.

Finally, I did not replace the trigger or tinker with it. I know how to setup a shot and I know how to shoot. I find the Crosman trigger to be adequate, it does not make me a poorer or better marksman. So I did not bother with it except to clean and lube it with Fluid Film.

Major hint to Crosman: do something about the crowning of the barrel. It is the single greatest improvement factor you can make to the accuracy. Better still, offer what I built as a basic high accuracy sporting rifle in 0.22, I think you would do well with such a product.

See ya.

dorikaze · New Member

ever thought about geting a difrent spring, and i can tell you how to mod the trigger with out costing anything.

Apollo · Member

dorikaze · New Member

Please follow these steps

1 - Remove the 3 screw that hold the whole asymebly together.

after you have you have the scope and the 3 screws removed, take off the 2 stage screw and the plastic peace here.

3 - bend the spring into the triger useing a pair of needle nose pliers.

4 re asymble and try it out.

this will make your triger from a i think 25lb pull stoc, to about 10lb and increse you accurate shots.
I did this to my own Crossman and it works awsome.

Please be advised that this for informational info only so blame me if it screws up your gun and or hurt somebody.

cw · Banned

25 POUND trigger pull!!!!!!!!!!!!!! I can't stand one that's
over 4 lbs.

Dorikaze, Your camera was focused onyour feet and not
the part that you were trying to illustrate.